void get_prog_point(CPUState* cpu, prog_point *p) {
CPUArchState* env = (CPUArchState*)cpu->env_ptr;
if (!p) return;
// Get address space identifier
target_ulong asid = panda_current_asid(ENV_GET_CPU(env));
// Lump all kernel-mode CR3s together
if(!in_kernelspace(env))
p->cr3 = asid;
// Try to get the caller
int n_callers = 0;
n_callers = get_callers(&p->caller, 1, cpu);
if (n_callers == 0) {
#ifdef TARGET_I386
// fall back to EBP on x86
int word_size = (env->hflags & HF_LMA_MASK) ? 8 : 4;
panda_virtual_memory_rw(cpu, env->regs[R_EBP]+word_size, (uint8_t *)&p->caller, word_size, 0);
#endif
#ifdef TARGET_ARM
p->caller = env->regs[14]; // LR
#endif
}
p->pc = cpu->panda_guest_pc;
}
static stackid get_stackid(CPUArchState* env) {
#ifdef USE_STACK_HEURISTIC
target_ulong asid;
// Track all kernel-mode stacks together
if (in_kernelspace(env))
asid = 0;
else
asid = panda_current_asid(ENV_GET_CPU(env));
// Invalidate cached stack pointer on ASID change
if (cached_asid == 0 || cached_asid != asid) {
cached_sp = 0;
cached_asid = asid;
}
target_ulong sp = get_stack_pointer(env);
// We can short-circuit the search in most cases
if (std::abs(sp - cached_sp) < MAX_STACK_DIFF) {
return std::make_pair(asid, cached_sp);
}
auto &stackset = stacks_seen[asid];
if (stackset.empty()) {
stackset.insert(sp);
cached_sp = sp;
return std::make_pair(asid,sp);
}
else {
// Find the closest stack pointer we've seen
auto lb = std::lower_bound(stackset.begin(), stackset.end(), sp);
target_ulong stack1 = *lb;
lb--;
target_ulong stack2 = *lb;
target_ulong stack = (std::abs(stack1 - sp) < std::abs(stack2 - sp)) ? stack1 : stack2;
int diff = std::abs(stack-sp);
if (diff < MAX_STACK_DIFF) {
return std::make_pair(asid,stack);
}
else {
stackset.insert(sp);
cached_sp = sp;
return std::make_pair(asid,sp);
}
}
#else
return panda_current_asid(ENV_GET_CPU(env));
#endif
}
static bool returned_check_callback(CPUState *env, TranslationBlock* tb){
// First, check if any of the PANDA VMI callbacks needs to be triggered
#if defined(CONFIG_PANDA_VMI)
panda_cb_list *plist;
for(auto& retVal :fork_returns){
if (retVal.retaddr == tb->pc && retVal.process_id == get_asid(env, tb->pc)){
// we returned from fork
for(plist = panda_cbs[PANDA_CB_VMI_AFTER_FORK]; plist != NULL; plist = plist->next) {
plist->entry.return_from_fork(env);
}
// set to 0,0 so we can remove after we finish iterating
retVal.retaddr = retVal.process_id = 0;
}
}
fork_returns.remove_if(is_empty);
for(auto& retVal :exec_returns){
if(retVal.process_id == get_asid(env, tb->pc) && !in_kernelspace(env)){
//if (retVal.retaddr == tb->pc /*&& retVal.process_id == get_asid(env, tb->pc)*/){
// we returned from fork
for(plist = panda_cbs[PANDA_CB_VMI_AFTER_EXEC]; plist != NULL; plist = plist->next) {
plist->entry.return_from_exec(env);
}
// set to 0,0 so we can remove after we finish iterating
retVal.retaddr = retVal.process_id = 0;
}
}
exec_returns.remove_if(is_empty);
for(auto& retVal :clone_returns){
if (retVal.retaddr == tb->pc && retVal.process_id == get_asid(env, tb->pc)){
// we returned from fork
for(plist = panda_cbs[PANDA_CB_VMI_AFTER_CLONE]; plist != NULL; plist = plist->next) {
plist->entry.return_from_clone(env);
}
// set to 0,0 so we can remove after we finish iterating
retVal.retaddr = retVal.process_id = 0;
}
}
clone_returns.remove_if(is_empty);
#else
fork_returns.clear();
exec_returns.clear();
clone_returns.clear();
#endif
//check if any of the internally tracked syscalls has returned
//only one should be at its return point for any given basic block
bool invalidate = false;
for(auto& retVal : other_returns){
if(retVal.retaddr == tb->pc && retVal.process_id == get_asid(env, tb->pc)){
Callback_RC rc = retVal.callback(retVal.opaque.get(), env, retVal.process_id);
if(Callback_RC::INVALIDATE == rc){
invalidate = true;
} else if(Callback_RC::NORMAL == rc){
retVal.retaddr = retVal.process_id = 0;
} else if(Callback_RC::ERROR == rc){
fprintf(stderr, "Syscalls caused an error\n");
assert(0);
} else {
fprintf(stderr, "Unknown syscalls internal callback return value\n");
assert(0);
}
}
}
other_returns.remove_if(is_empty);
return invalidate;
}
